• Journal of the Korean Orthopaedic Association
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• v.54 no.1
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• pp.59-66
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• 2019

Purpose: Several radiologic reference lines have been used to evaluate individuals with a clubfoot but there is no consensus as to which is most reliable. The aim of this study was to identify which radiologic parameters have relevance to the predictability of additional surgery after Ponseti casting on clubfoot and the effect of clubfoot treatments that contain Ponseti casting and additional surgery. Materials and Methods: A total of 102 clubfeet (65 patients, 37 bilateral) were reviewed from 2005 to 2013. The patients were divided into two groups (Group A, those for whom the result of the Ponseti method was successful and did not require additional surgery; and Group B, those for whom the result of the Ponseti method was unsuccessful and required additional surgery), and the following parameters were measured on the plain radiographs: i) talo-calcaneal angle on the anteroposterior and lateral view, ii) talo-1st metatarsal angle on the anteroposterior view, and iii) Tibio-calcaneal angle on the lateral view with the ankle full-dorsiflexion state. Each radiograph was reviewed on two separate occasions by one orthopedic doctor to characterize the intra-observer reliability, and the averages were analyzed. Next, 20 cases were chosen using a random number table, and two orthopedic doctors measured the angle separately to characterize the interobserver reliability. Results: Groups A and B included 73 clubfeet (71.6%) and 29 clubfeet (28.4%), respectively. The initial talo-calcaneal angle and tibiocalcaneal angle in the lateral view were significantly different among the groups. In addition, inter- and intra-observer biases were not detected. The talo-1st metatarsal angle on the anteroposterior view and tibio-calcaneal angle on the lateral view were significantly different after treatment in both groups. Conclusion: Congenital clubfeet treated with the Ponseti method showed successful results in more than 70% of patients. The initial talocalcaneal angle and tibio-calcaneal angle on the lateral view were the radiologic parameters that could predict the need for additional surgical treatments. The talo-1st metatarsal angle on the anteroposterior view and tibio-calcaneal angle on the lateral view could effectively evaluate the changes in clubfoot after treatment.

• Journal of Broadcast Engineering
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• v.19 no.4
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• pp.521-532
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• 2014

ATSC-M/H based hybrid 3DTV, which is one of the service compatible 3DTV system, has considerable quality gap between the left and right views. And CRA(Conditional Replenishment Algorithm) has been proposed to deal with the issue of resolution mismatch and improve the visual quality. In CRA, the disparity vectors of stereoscopic images are estimated. The disparity compensated left view and simply enlarged right view are compared and conditionally selected for generating the enhanced right view. In order to implement CRA, a fast algorithm is strongly required because the disparity vectors need to be obtained at every layer and the complexity of CRA is quite high. In this paper, we adopted SDSP(Small Diamond Search Pattern) instead of full search and predicted the initial position of search pattern by examining the spatio-temporal correlation of disparity vectors and also suggested the SKIP mode to limit the number of processing units. The computer simulation showed that the proposed fast algorithm could greatly reduce the processing time while minimizing the quality degradation of reconstructed right view.

• Journal of the Korean association of regional geographers
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• v.10 no.3
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• pp.497-510
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• 2004

This study searched for comparison with geography of Qing China, origin of geographical name, people's feature and costume, description on regional geography, and perception on locality on view of a geographer, Ji-Won Park, a renowned Korean scholar of practical learning on the late 18th century. This study on the first three chapters of his Yorha Ilgi - "Crossing the Amnok(Yalu) River("渡河錄")," "Several Records on Senyang("監京雜識")," and "Writing Essays, Riding Horses("馹迅隨筆")," focusing on landscape of Qing China, inquiry on geographical name, feature and costume, and descriptions on locality, gives a glimpse on Park's geographical view on geography of Qing China. His writing style to compare landscapes between Korea and Qing China, full of his love for Korean landscape, is very delicate and clear, Although he sentimentalized when he passed through Bonghwang-castle(鳳凰城) in China, his subtle and beautiful writing explains that land and mountains in Han-yang(Seoul) are much more wonderful than those in China. His vivid depiction of landscape and weather on his way in Qing China is remarkable and explanation on geographical names like Parhae(渤海), Yoha(遼河), Taejaha(太子河), Senyang(瀋陽) etc. is enough to stimulate readers' curiosity on geography.

• Earthquakes and Structures
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• v.19 no.3
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• pp.157-174
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• 2020

The in-situ pushover test differs from the shake-table test because it is performed outdoors and thus its size is not restricted by space, which allows us to test a full-size building. However, to build a new full-size building for the test is not economical, consequently scholars around the world usually make scale structures or full-scale component units to be tested in the laboratory. However, if in-situ pushover tests can be performed on full-size structures, then the seismic behaviors of buildings during earthquakes can be grasped. In view of this, this study conducts two in-situ pushover tests of reinforced concrete (RC) buildings. One is a masonry-infilled RC building with openings (the openings ratio of masonry infill wall is between 24% and 51%) and the other is an RC building without masonry infill. These two in-situ pushover tests adopt obsolescent RC buildings, which will be demolished, to conduct experiment and successfully obtain seismic capacity curves of the buildings. The test results are available for the development or verification of a seismic evaluation model. This paper uses ASCE 41-17 as the main evaluation model and is accompanied by a simplified pushover analysis, which can predict the seismic capacity curves of low-rise buildings in Taiwan. The predicted maximum base shear values for masonry-infilled RC buildings with openings and for RC buildings without masonry infill are, respectively, 69.69% and 87.33% of the test values. The predicted initial stiffness values are 41.04% and 100.49% of the test values, respectively. It can be seen that the ASCE 41-17 evaluation model is reasonable for the RC building without masonry infill walls. In contrast, the analysis result for the masonry infilled RC building with openings is more conservative than the test value because the ASCE 41-17 evaluation model is limited to masonry infill walls with an openings ratio not exceeding 40%. This study suggests using ASCE 41-17's unreinforced masonry wall evaluation model to simulate a masonry infill wall with an openings ratio greater than 40%. After correction, the predicted maximum base shear values of the masonry infilled RC building with openings is 82.60% of the test values and the predicted initial stiffness value is 67.13% of the test value. Therefore, the proposed method in this study can predict the seismic behavior of a masonry infilled RC frame with large openings.

• The Journal of The Korea Institute of Intelligent Transport Systems
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• v.20 no.5
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• pp.35-44
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• 2021

In recent times, several studies have been conducted focusing on crashes occurring on the main segment of the highway. However, there is a dearth of research dealing with traffic safety relating to other highway facilities, especially ramp areas. According to the Korea Expressway Corporation's Expressway Information Service, 6,717 crashes have occurred on ramps in the five years from 2015~2019, which accounts for about 15% of all highway accidents. In this study, the simple and full safety performance functions (SPFs) were evaluated and explored using different statistical distributions (i.e., Poisson Gamma (PG) and Poisson Inverse Gaussian (PIG)) and techniques (i.e., fixed effects (FE) and random effects (RE)) to provide more accurate crash prediction models for highway ramp sections. Data on the geometric characteristics of traffic and roadways were collected from various systems and with extensive efforts using a street-view application. The results showed that the PIG models present more accurate crash predictions in general. The results also indicated that the RE models performed better than FE models for simple and full SPFs. The findings from this study offer transportation practitioners using the Korea Expressway Corporation's Expressway a dependable reference to enhance and understand traffic safety in ramp areas based on accurate crash prediction models and empirical evidence.

• Journal of Dental Rehabilitation and Applied Science
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• v.17 no.4
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• pp.257-274
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• 2001

To properly prepare teeth, dentists require a direct view of the working area and are often placed in a difficult position, moreover, a high proportion of dentists suffer from headache and back pain. Dentists who make use of the dental mirror and position their patients carefully to gain a proper view report less headache, pain and discomfort in the shoulders. It is recommended that dentists learn the "Home Position(H.P.)" which among the various "Random Position(R.P.)" methods, enables dentists to approach their patients in a stable posture. The purpose of this study was to compare tooth preparation in the H.P. and the R.P., and evaluate the clinical efficacy of the H.P.. Tooth preparation for a full cast crown was performed on the maxillary left 1st molar using the H.P. and the R.P., and the shapes of the prepared tooth surfaces at the two different operating positions were compared. The amount of occlusal reduction, marginal width, height, and axial taper were measured and analyzed. A T-test was performed separately to compare the results of the H.P. and the R.P. with respect to the accuracy of the corresponding tooth reduction. The results were as follows. ; 1. The amount of occlusal reduction was excessive on the mesiobuccal cusp(P<0.05), and deficient on the lingual cusp in the H.P.(P<0.01). In the R.P., this was excessive on the buccal cusp and deficient on the fossa and distolingual cusp(P<0.01). 2. The amounts of marginal width were excessive in all areas except on the lingual and mesial surfaces in the H.P. and lingual surface in the R.P.(P<0.01). 3. The marginal heights were achieved more accurately in the R.P. than the H.P.(P<0.01). 4. Axial surface taper was excessive in all areas in the H.P.(P<0.01). But the axial taper of measured areas was even, and tooth is more like to retain its original axis after reduction. In the R.P., axial surface taper was excessive on the mesial and buccal area, and deficient on the distolingual area(P<0.01), and therefore, the axis of the prepared teeth was tipped in the distolingual direction. 5. The times needed for preparation were 12 minutes and 49 seconds in the H.P., and 11 minutes and 35 seconds in the R.P., and the R.P. was statistically faster(P<0.01). The tooth preparation in the H.P. achieved its goal, in that it enabled the operator to make even tooth reduction. In conclusion, the H.P. system offers an improved method that can be used in clinic after specific training.

• Journal of Korean Ophthalmic Optics Society
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• v.18 no.4
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• pp.503-507
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• 2013

Purpose: This study was to design wide angle mobile camera corrected optical distortion for peripheral area, which were reduced optical distortion and TV distortion by using 4 aspherical lenses. Methods: The optical design was satisfied with ${\pm}1%$ optical distortion in viewing angle of $95^{\circ}$ and total length of optical system was less than 4.5 mm which was considering a thickness of mobile camera. 1/3.2 inch (5M) CCD sensor was used in the optical system and set design condition to satisfy MTF which was over than 20% in 140 lp/mm. Results: Optimized wide angle mobile camera showed ${\pm}1%$ optical distortion in full field of $95^{\circ}$ viewing angle and TV distortion was 0.46% so that distortion of peripheral area was reduce. MTF showed over than 20% in every field. Ray aberration and astigmatism were small amount so that it showed stable performance. Conclusions: Obtain wider and clearer view which is reduced image distortion of surrounding area via optical method in wide angle mobile camera which has wider view angle than current mobile camera. And it was able to fix a demerit when it occurred via software correction. It is able to apply to study of camera which is related to spectacles.

• Journal of Korean Ophthalmic Optics Society
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• v.19 no.1
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• pp.79-85
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• 2014

Purpose: This study investigated accommodative changes by measuring accommodative response, appearing on the normal and convergence insufficiency Group, by using both eyes open-view auto-refractometer (Nvision-K5001, shin-nippon, Japan). Methods: It carried out objective and subjective refractions, targeting 74 college students (54 males and 20 females) aged between 19 and 29 ($21.59{\pm}2.53$), spherical equivalent OD $-2.28{\pm}2.03$ D, OS $-2.18{\pm}2.01$ D, by measuring accommodative responses at full correction and under correction with plus lens +0.25, +0.50, +0.75 arbitrarily added. Results: In the group of normal and convergence insufficiency, the shorter fixation distances were, the greater accommodative lags showed. The group of convergence insufficiency showed the lesser changes of accommodative response than those of normal. But we found that the convergence insufficiency group had a little larger accommodative amplitude in the total fixation distances. The full correction of convergence insufficiency group and the under correction (+0.50 D) of normal were alike in the accommodative responses. We have also investigated that the correlation between accommodative responses and fixation distances was decreased steeply at the excessive low vision correction. Conclusions: Under correction (+0.50 D) in a near distance is expected to avoid unnecessary accommodative responses, make eyes relaxed and comfortable.

• Journal of Broadcast Engineering
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• v.19 no.5
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• pp.616-626
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• 2014

In this paper, we introduce a real-time stereo-to-multiview conversion system using FPGA and GPU. The system is based on two different devices so that it consists of two major blocks. The first block is a disparity estimation block that is implemented on FPGA. In this block, each disparity map of stereoscopic video is estimated by DP(dynamic programming)-based stereo matching. And then the estimated disparity maps are refined by post-processing. The refined disparity map is transferred to the GPU device through USB 3.0 and PCI-express interfaces. Stereoscopic video is also transferred to the GPU device. These data are used to render arbitrary number of virtual views in next block. In the second block, disparity-based view interpolation is performed to generate virtual multi-view video. As a final step, all generated views have to be re-arranged into a single image at full resolution for presenting on the target autostereoscopic 3D display. All these steps of the second block are performed in parallel on the GPU device.

• Proceeding of Spring/Autumn Annual Conference of KHA
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• 2009.11a
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• pp.17-22
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• 2009

This research was conducted to investigate methods to strengthen the apartment community from the territoriality point of view. In order to achieve this goal, first of all the concept and the structure of territoriality are studied through articles and literature reviews to ensure a full understanding of the community strengthening-related plan elements suggested in the previous research. The study is then divided into the categories of semi-private territory and semi-public territory to pursue analysis based on the issues related to strengthening community such as possession, proximity, defense, boundary-regulation, and personalization in case by case studies. The results of case studies are as follows: in the case of possession with psychological concept of possession, the extension of private space and exclusive space are suggested. And for the concept of proximity, that is, the physical and psychological distance for sense of the same nature, increased opportunity of meeting the residents in the same building or same area are suggested And for the psychological proximity, familiar design and facilities for meeting and exchange-related methods are shown. For the case of indirect defense in defense concept, the methods related to monitoring and supervising facilities for protection are found. For the boundary-regulations, it is based on the concepts of physical and psychological borderlines; walls either vertical or horizontal, or such obstacle-related methods are suggested for the physical borderline, and space structure and symbols-related methods are found for psychological borderline. Finally, for the case of personalization which is related to the expression of identity, design-related methods are suggested.